Myectomy and Obstruction vs. Sudden Death Risk

[mtlieb]

Lisa, et al.

Three questions:

1.) It has been mentioned previously on the board that following a myectomy your risk of sudden death decreases dramatically. Apparently this was discussed at the annual meeting and was included in a paper given by one of our specialists. Could you provide a specific reference to this material, whether it be from meeting notes or the actual study from which this finding has been derived? I have been unable to locate the source material myself.

2.) To address in part a question previously asked by Michael Obrien regarding obstruction and sudden death: If myectomy does in fact decrease the risk of SCD, does this not indicate then that the obstruction itself presented a specific SCD risk? Or does the myectomy simply resolve issues related to sudden death that are inherent to all HCM'ers, obstructed or not?

3.) It is my understanding that following a myectomy the electrical pathways through the septum are further disrupted by the surgery itself. I assume that this is why many patients experience rhythm disturbances after surgery which require pacing and/or an ICD, and in fact there are persons on the board here who did not receive ICD's until after they had undergone their myectomies. This being the case, how does this relate to the issue of sudden death? Given the changes made to the conducting tissues and the resulting rhythm problems, one would think that the risk of sudden death would actually increase post-myectomy rather than decrease. Please comment on this if possible.

Thanks,

Jim

[Burton Borrok]

Hey Jim,

Your post myectomy slowness of thought seems to have resolved itself.

Heavy thinking my friend – proud to know you.

Burt

[Lisa Salberg]

Jim,
I am sitting at home right now - Sunday Morning at Lisa Kitchen Table! So I do not have all my data here. I can however tell you this:
It is currently believed that a lower (under 30mm) or NO gradient is good/better for the heart and data shows the long term survival is BETTER for those with low or no gradients - this is for those who never had a gradient and those post myectomy.
Further, there is no data showing that post myectomy Pt's have a greater risk of arrhythmia in the long term- thus the better long term survival. Many people who have ICD's post myectomy have other risk factors that make them a candidate for such treatment.
The issues regarding Post Alcohol septal ablation and pro arrhythmic activity is still under investigation - but appears at this point to be a significant matter that needs attention - and may in fact be a risk factor for SD. More research is need to know for sure - thus the caution in doing the procedure in the young.

Does this being to answer your questions?

Lisa

[vmcmahon]

3 Questions

Hi all - Would it be possible to have this discussed in more detail in the AGM..? they are very in teresting questions...

thnx

Vinnie

[mtlieb]

Lisa, in regard to Question 1 then... there are no data to support the claim that myectomy reduces the risk of sudden death specifically?

Thanks,

Jim

[Burton Borrok]

Golly Jiminy Jim,
If a person has a myectomy and the stress on the heart is reduced – who’s to say that a SCD episode will not take his life, or if he did not have a myectomy who’s to say an SCD episode will?

We can only go by inductive reasoning. Specifically, if the stress on the heart is reduced it is reasonable to assume that the chance of an SCD episode will also be reduced – not eliminated but reduced. Actually, I am a bit surprised that no study has been performed following two groups of people with the same basic exposure to SCD. One group comprised of those who chose to have a myectomy and the other, those who didn’t. Over time we could then quantify the percentage of people in the two groups who experienced an SCD episode – and further, the number of people in the two groups who survived the SCD experience. Then we could also determine the percentage of the survivors who were saved with the use of an implanted defibrillator.

It kind of sounds like trying to determine how many angles can dance on the head of a pin though, doesn’t it? People have myectomies to ‘cure / resolve’ obstructions and improve their quality of life. They have defibrillators implanted for protection from an SCD episode.

What would you think if your cardiologist said that all your examinations and tests indicate that you should have a defibrillator, but since you had a myectomy you really don’t need it? If I were his patient – he just might scare me into an SCD episode right there and then.

And your choice my friend is what – an apple or an orange?
Burt

[Eileen2345]

I know a young lady in her early 30's who had a myectomy, she has an ICD and it has shocked her heart due to v-fib.

I don't know though.

[Pam Alexson]

I think a key word in definition here is that an AICD, CAN help to prevent SCD, it does not prevent sudden SCD from occurring. Everyones heart is different with regards to HCM. The disease process could be that irregardless of the AICD a simple devise will not bring the heart back to NSR if the heart is failed beyond hope.

When I had my myectomy , my mom asked the doctors if I would need to keep my dedibrilator. Long explanation short, they said yes, I have been dettermined to have risk factors of SCD irregardless of the obstruction, and I never had a very big septum, but I had a large gradient. Neither of my cousins who died had obstructions, or history of murmurs.

Myectomy or ablations do not prevent the risk of SCD. Many individuals who are non- obstructed have been SCD victims. They do help to prevent worsening CHF by removal of the gradient. Therefore it can be theorized that this can help to lessen a worsening heart disease. ( but not in all cases). We do know that CHF does severly impact the hearts health and functioning , so anything that can slow that down can only help preserve function and lessen deleterious outcomes. Sounds reasonable right?

There are articles and studies about the importance of earlier intervention to help prevent worsening CHF. Dr Martin Maron is one of the authors I think it may even be listed somewhere on this site.

[mtlieb]

Okay, i appreciate the replies everybody, but please allow me to redirect the questioning here before this thing gets all muddied up. The answer i'm looking for is quite simply a YES or NO. Pam has come the closest thus far, so congratulations my dear... you win the lollipop.

Maron, et al. studied the long-term outcomes of obstructed HCM patients with gradients of 30 mmHg or greater. In these cases, myectomy has been shown to improve the long-term prognosis and progression into heart failure and eventual death. This is well documented. I've read the study here on the site a hundred times probably. Post-myectomy, the survival rate of obstructed patients is similar to that of those who have no obstruction at all. Okay. I get that.

Sudden cardiac death however as you all know is an entirely different beast, and i'm wondering if the Maron study broke these data down in this manner. Prospective myectomy patients on this site have in fact been told that the surgery will reduce their chances of SCD. Quite simply, i would like to know if we have data to support that. That's why i asked Lisa or anyone else to please reference a study that has shown this to be fact. Otherwise, we are giving out mis-information.

So... i will pose the question again:

Are there any data to support the claim that myectomy reduces the risk of sudden death specifically?

Thanks much... your input is greatly appreciated.

Jim

[Toogoofy317]

Jim,

I did quite an extensive search tonight on your question. My answer would be no. In my opinion it seems like SCD would be more prominent after a myectomy than before. Simply, because muscle is being cut out and that could interfere with an electrical pathway. Hence, why they place temporary leads after the surgery It is also in this light that I cannot conclude that it could decrease it either. Since, there is myocardial disarrayment on the cellular level you could not theoretically cut it all out because you don't know where it is. If these disarrayed cells were only in the area that was removed then yeah I guess you could remove the chance of disturbance.

Now, myectomy can reduce other causes of cardiac insufficiencies such as CHF, and progression to burnt-out hcm. So it does have a great prognostic value there. I believe the best bet on SCD though is to follow the five guidlines for AICD placement. You know them so I won't repeat them.

Mary S.

[felixdacat]

I think that some of my past posts may have contributed to Jim’s question (jeez what an ego).
I swear that I saw a slide during a presentation at the 2004 annual meeting that compared the rate of sudden death for Post-Myectomy patients and the general public. They were a match.
I can no longer remember if the presentation was by Barry Maron or the surgeon from the Mayo (Deanni?).
Can someone help me out here (Reenie, Lisa???).
But this thread does bring up another question.
Are post Myectomy patients (and I guess post ablation patients) considered to have HCM w/o obstruction (since they no longer have an obstruction), or are they still considered HOCM patients? In other words, what are the treatment options available to post procedure HOCM patients if they still have some symptoms?
A good example would be our gal Shirley. Is the reason she’s on a transplant list because they now consider her an HCM w/o obstruction patient, or is her case just too complicated to be an example at all?

[Reenie]

Felix, I remember what you're talking about but I can't remember enough details to say what the slide show and presentation said. I would think that you are without obstruction once you've had a procedure to remove obstruction. Shirley, as an example, has said that they're wanting to put her on the transplant list because her heart has become too stiff to work well. (Shirley, please correct me if I'm wrong here.) Good questions, though. I've stayed out of this conversation for the most part because I can't intellectually add anything to it. (Hey, no comments from the cheap seats! You know who you are....) My knowledge is too limited to offer any insight on the matter.

Reenie

[mtlieb]

Lisa, in regard to Question 1 then... there are no data to support the claim that myectomy reduces the risk of sudden death specifically?

Thanks,

Jim

[Lisa Salberg]

There is data that has shown that those with obstruction do not live as long as those with out obstruction. Thereby it is better to not have obstruction. Those who have had myectomy have a similar life spans as those without obstuction. Those with alcohol ablation have shown an increase in ICD discharge post procedure.

Does this answer the question.

Lisa

[Toogoofy317]

So,

Let me see if I got this. SO if you have an ablation you are at higher risk for SCD? Is there a specific etiology behind that (e.g alcohol disrupts more pathways). If you have a myectomy are the prevalence of SCD higher, lower or the same as if you were non-obstructed to begin with?


Just curious,

Mary S.